This has happened to me twice, almost exactly the way you see it in the video
The first time was around 45 mph and I wasn't wearing a helmet (CA didn't have a helmet law at the time, a lot of things changed here while I was away
) I was in jeans and a t-shirt.
It cost me some knee issues when I put it through the passenger window and bent the frame.
The second time I was going almost 60, I flew about three times the distance as the guy in the video and landed flat on my back, I didn't get up as fast as he did that time.
Also in jeans and t-shirt, road rash won't kill you but shit if fucking STINGS!
I also didn't get a single scratch on my helmet.
The second one I feel in my lower back every single day, I quit riding for 20 years because of that accident.
But then I realized that life was too short to worry about "what if it happened again?"
So now I am a super defensive rider, but I still don't like riding in town in traffic.